In the technical field of actuator controlled valves and a mechanical connection between a valve and a valve controlling actuator, described below is a coupling element for connecting an actuator to a valve in an actuator system for controlling the valve. Also described are a valve system, which includes the valve and the actuator system, and a method for connecting such a coupling element to an actuator.
It is known to regulate the temperature of rooms within a building by an actuator, which is connected to a valve controlling the flow rate through the interior of a radiator. Typically, the corresponding flow medium is hot water. When the hot water flows through the radiator, it transfers thermal energy to the radiator.
For controlling the position of radiator valves in particular electromechanical actuators are used. A correct operation of such a valve system having an actuator and a radiator valve relies on a stable mechanical connection between the actuator and the valve. Such a connection is usually established by a coupling element. Typically the coupling element is connected to the actuator in a non-detachable but rotatable manner. In the following an assembly that includes the actuator and the coupling element connected to the actuator will be referred to as an actuator system.
The coupling element may be a nut having an inner thread, which is suitable for engaging with an outer thread respectively a male thread of a valve body. Therefore, when mounting the actuator system to the valve body the nut has to be rotated at least with respect to the valve body.
When assembling the actuator system the nut has to be kept exactly in the axial position of the actuator. In order to provide for a rotatable connection between the nut and the actuator it is known to use plastic snapping hook elements being formed at the actuator in order to grip into a groove of the nut. Such hook elements typically allow for an easy assembling procedure for the actuator system. However, hook elements have the disadvantage that they can brake easily if the nut is tighten too hard.
Siemens Building Technologies introduced a much more stable solution for mechanically connecting a nut to a valve body. In the data sheet 4893 describing Electrical Actuators SSA31 . . . , SSA81 . . . and SSA61 . . . for radiator valves VDN . . . , VEN . . . , VUN . . . , VPD . . . and VPE . . . , CE1N4893en, dated Feb. 23, 2005 (see www.sbt.siemens.ru/files/13093.pdf, there are disclosed electrical actuator systems having a wire situated between an annular grove of the nut and a grove of an actuator neck. The disadvantage of this solution is the complicated manufacturing process. The first pass yield is too low and an automatic assembly of corresponding actuator systems is hardly possible.
There may be a need for providing a simple but mechanically stable connection between an actuator and a valve.